1) If installing or replacing the distributor, follow the vehicle/engine factory service manual instructions (Ford TFI: LINK, LINK, LINK/GM HEI: LINK). Temporarily disable the "Idle Spark" control (in Idle Settings), so the idle timing doesn't fluctuate rapidly when viewed with a timing light. Without disconnecting anything, start the engine, and turn the distributor to synchronize the engine's initial (idle) timing using a timing light. Ensure there aren't any active 'timing modifiers' at this point (e.g. Timing vs Coolant Temperature, Timing vs Manifold Air Temperature, Knock Retard, etc.). Also, ensure you don't have any erroneously programmed "Warning Enabled Timing Offset" parameters in the "Sensor Scaling/Warnings" (System ICF) or in the custom Inputs (Inputs/Outputs ICF) or in the Advanced 1D/2D Tables (Advanced ICF). If you're not sure, use the EFI software "Enable Static Timing Set" (in the "Sync With ECU" icon, drop down menu - top Toolbar). When the initial (idle) timing is synchronized, lock down the distributor's adjustment bolt and never touch it again for this purpose.
TIP: If you're unsure about the initial distributor installation/positioning, or you'd like to verify the base timing before starting the engine, it's suggested to temporarily disconnect the fuel injector harness, and crank the engine while viewing the Cranking Timing with a timing light. This prevents the engine from starting, but still allows you to adjust & confirm the base timing (engine safety). When the Cranking Timing is correct (synchronized), the timing at idle will be too.
When you're cranking the engine (with the injector harness disconnected), sync at 15° or whatever your Cranking Timing is.
When you're idling the engine (without disconnecting anything), sync at 25° or whatever your idle timing on your Timing Table is.
FYI: Just like a carbureted application, if your distributor (or cam sync unit) ends up facing the "wrong" direction (aesthetics or clearance reasons), you can remove the distributor assembly from the engine and reinstall it in the position you like without turning the inner shaft. On some engine applications, you may have to turn the oil pump driveshaft to properly engage the distributor shaft. You can remove the distributor cap and loosely tape the rotor to the distributor body for maintaining the alignment.
2) After synchronizing the initial timing (distributor hold-down bolt tight), ALL timing adjustments & tuning is done on the laptop computer. Next, use the EFI software "Enable Static Timing Set" (in the "Sync With ECU" drop down menu - top Toolbar). I use a Static Timing value of 25° or 30°. Adjust the "Inductive Delay" setting to synchronize the timing advance when the engine is revved to higher RPM (momentary 4000 RPM is fine). To change the "Inductive Delay", the EFI software can't be in "Online" mode. Turn the engine off, adjust the value, "Save" the change, turn the key on and "Send To ECU". Cycle the key again and restart the engine each time. When correctly adjusted, the ECU should maintain the Static Timing value when revving the engine; simulating locked-out timing advance. Afterwards, deactivate the EFI software "Enable Static Timing Set" & enable the "Idle Spark" control. Verify the ignition timing is synchronized throughout the RPM range, and you're done.
• Think of the "Ignition Reference Angle" as just a EFI software setting; no adjustment or tuning is necessarily required.
(Don't be lazy...turn the distributor to synchronize the timing at idle speed, as opposed to changing the Reference Angle or Timing Offset.)
With a GM HEI & Ford TFI, simply set it to 10° and forget about it (it's not your idle timing).
Magnetic & Hall-Effect distributors without modules (ignition box required), set to 50°-60°.
Crank trigger users (Magnetic & Hall-Effect): Read Addendum below - also set to 50°-60°.
For further information on setting up Magnetic & Hall-Effect crank triggers/distributors (no modules):
http://forums.holley.com/showthread....p-Instructions (Magnetic & Hall-Effect Crank/Cam Sensor Setup Instructions)
Conversely, the "Inductive Delay" needs to be adjusted to synchronize the timing at higher RPM.
10° Ignition Reference Angle is correct for GM HEI & Ford TFI. The GM HEI & Ford TFI distributors are installed at 10° Ignition Reference Angle, but they're
operating one crank revolution ahead, so they're retarding a lot. On a high RPM race engine, it's best to keep the amount of ignition retard (occurring from
such an advanced reference angle) to a minimum, so it's not used on expensive race engines. Of course, timing accuracy is better with a crank trigger.
http://www.masterenginetuner.com/top...all-fails.html (Crank Reference Angle Importance)
Holley EFI HyperSpark Distributor:
Reference Angle ― "57.5°" (← Inherent Ignition Reference Angle & rotor-phasing of this unit.)
Inductive Delay ― "100.0 usec" (← Synchronization info, adjusted per application.)
Holley EFI Dual Sync Distributor:
Reference Angle ― "50°" (← Inherent Ignition Reference Angle & rotor-phasing of this unit.)
Inductive Delay ― "100.0 usec" (← Synchronization info, adjusted per application.)
ADDENDUM: With a crank trigger, turning the distributor only adjusts rotor phasing.
(Read how to check & adjust rotor phasing further below on this page.)
The crank sensor sliding bracket, now does the task that turning the distributor once did.
http://www.dragstuff.com/techarticle...ger-setup.html (Crank Trigger Setup & Information)

https://www.jcna.com/ignition-advanc...requirements-0 (Ignition Advance Curve Factors)
TIP: If you're unsure about the initial distributor installation/positioning, or you'd like to verify the base timing before starting the engine, it's suggested to temporarily disconnect the fuel injector harness, and crank the engine while viewing the Cranking Timing with a timing light. This prevents the engine from starting, but still allows you to adjust & confirm the base timing (engine safety). When the Cranking Timing is correct (synchronized), the timing at idle will be too.
When you're cranking the engine (with the injector harness disconnected), sync at 15° or whatever your Cranking Timing is.
When you're idling the engine (without disconnecting anything), sync at 25° or whatever your idle timing on your Timing Table is.
FYI: Just like a carbureted application, if your distributor (or cam sync unit) ends up facing the "wrong" direction (aesthetics or clearance reasons), you can remove the distributor assembly from the engine and reinstall it in the position you like without turning the inner shaft. On some engine applications, you may have to turn the oil pump driveshaft to properly engage the distributor shaft. You can remove the distributor cap and loosely tape the rotor to the distributor body for maintaining the alignment.
2) After synchronizing the initial timing (distributor hold-down bolt tight), ALL timing adjustments & tuning is done on the laptop computer. Next, use the EFI software "Enable Static Timing Set" (in the "Sync With ECU" drop down menu - top Toolbar). I use a Static Timing value of 25° or 30°. Adjust the "Inductive Delay" setting to synchronize the timing advance when the engine is revved to higher RPM (momentary 4000 RPM is fine). To change the "Inductive Delay", the EFI software can't be in "Online" mode. Turn the engine off, adjust the value, "Save" the change, turn the key on and "Send To ECU". Cycle the key again and restart the engine each time. When correctly adjusted, the ECU should maintain the Static Timing value when revving the engine; simulating locked-out timing advance. Afterwards, deactivate the EFI software "Enable Static Timing Set" & enable the "Idle Spark" control. Verify the ignition timing is synchronized throughout the RPM range, and you're done.
• Think of the "Ignition Reference Angle" as just a EFI software setting; no adjustment or tuning is necessarily required.
(Don't be lazy...turn the distributor to synchronize the timing at idle speed, as opposed to changing the Reference Angle or Timing Offset.)
With a GM HEI & Ford TFI, simply set it to 10° and forget about it (it's not your idle timing).
Magnetic & Hall-Effect distributors without modules (ignition box required), set to 50°-60°.
Crank trigger users (Magnetic & Hall-Effect): Read Addendum below - also set to 50°-60°.
For further information on setting up Magnetic & Hall-Effect crank triggers/distributors (no modules):
http://forums.holley.com/showthread....p-Instructions (Magnetic & Hall-Effect Crank/Cam Sensor Setup Instructions)
Conversely, the "Inductive Delay" needs to be adjusted to synchronize the timing at higher RPM.
10° Ignition Reference Angle is correct for GM HEI & Ford TFI. The GM HEI & Ford TFI distributors are installed at 10° Ignition Reference Angle, but they're
operating one crank revolution ahead, so they're retarding a lot. On a high RPM race engine, it's best to keep the amount of ignition retard (occurring from
such an advanced reference angle) to a minimum, so it's not used on expensive race engines. Of course, timing accuracy is better with a crank trigger.
http://www.masterenginetuner.com/top...all-fails.html (Crank Reference Angle Importance)
Holley EFI HyperSpark Distributor:
Reference Angle ― "57.5°" (← Inherent Ignition Reference Angle & rotor-phasing of this unit.)
Inductive Delay ― "100.0 usec" (← Synchronization info, adjusted per application.)
Holley EFI Dual Sync Distributor:
Reference Angle ― "50°" (← Inherent Ignition Reference Angle & rotor-phasing of this unit.)
Inductive Delay ― "100.0 usec" (← Synchronization info, adjusted per application.)
![]() Ignition Timing Synchronization is an easy two step process using a timing light (Idle Spark control temporarily disabled). Ensure the ignition timing is fully synchronized. At idle (lock the distributor), and at higher RPM (Inductive Delay). https://forums.holley.com/showthread...ing-Holley-EFI (Ignition Timing Synchronization - A Two Step Process) ↑ Troubleshooting & synchronization verification information at the end of post # 1.↑ Read step # 2 "Inductive Delay": http://forums.holley.com/showthread....ing-Holley-EFI (Ignition Timing Synchronization) • Just to recap - Synchronizing the EFI timing (laptop) with the engine timing (timing light): NOTE: Temporarily disable the "Idle Spark" control (in Idle Settings). 1) Turn the distributor or adjust the crank trigger to synchronize the initial (idle) timing, then lock it down. Next, ensure timing is synchronized at higher RPM using the EFI software. NOTE: Now use the EFI software "Enable Static Timing Set". I use a Static Timing value of 25° or 30°. 2) Momentarily rev the engine, and watch the timing advance with your timing light. It shouldn't move. If timing advances or retards, adjust the "Inductive Delay" until the timing maintains itself. If the ignition timing retards, increase this value. If the timing advances, decrease this value. SUMMARY: The initial (idle) timing is synchronized by turning the distributor or adjusting the crank trigger, and locking it down. The timing at higher RPM is synchronized by adjusting the Inductive Delay in the EFI software. The first synchronization is physical, and the second synchronization is electronic (Inductive Delay). Believe the timing light above all else, it's always the real timing (if there's a discrepancy). When finished, the timing as viewed on the laptop, should match what you see with the timing light, at all RPM. Once the ignition timing is fully synchronized, the Timing Table can be tuned for each application. FYI: "Your Crank Sensor "Inductive Delay" value is greater than 50. This typically will result in over advanced ignition timing at high RPM with a Hall-Effect sensor. Make sure this value is correct." That's actually not what this warning message means. It means if left unsynchronized, the timing can advance beyond what the Timing Table specifies. That's just a warning message to ensure you synchronize the timing at higher RPM (Inductive Delay). After synchronizing the timing, ignore that warning message and never adjust the Inductive Delay again. With the Holley EFI software, you have the option to disable this warning message in Toolbox, Preferences. |
![]() The Ignition Reference Angle must be at least 10° higher than the maximum amount timing programmed in the Base Timing Table. The ECU needs an Ignition Reference Angle, so it can control the synchronized Base Timing Table. The Ignition Reference Angle (10° more than max timing requirement) doesn't change your programmed ignition timing in the Base Timing Table, but it does affect the inherent rotor-phasing (LINK) of the distributor for distributor type crank signal applications. The Ignition Reference Angle will be between 45°-75°, based on the engine hardware & application. http://www.masterenginetuner.com/top...all-fails.html (Crank Reference Angle Importance) Ensure the distributor's rotor-phasing is correct: http://documents.msdperformance.com/8644_tb.pdf (MSD Rotor-Phasing Document) With a crank trigger kit, turning the distributor only adjusts rotor phasing. MSD has a good video on why it's important: http://www.youtube.com/watch?v=aWMlNwGW0tM (MSD Tech Rotor-Phasing Video) For naturally aspirated engines, the rotor is usually phased halfway between minimum & maximum amount of timing advance used. For forced induction engines, the rotor is usually phased at maximum boost retard, because that's when cylinder pressure is the greatest. ![]() The ECU needs an Ignition Reference Angle, so it can control the ignition timing. Distributor type crank signal: For a distributor, this is built into the design and takes into account rotor-phasing. Missing tooth crank trigger: The TDC Tooth Number (amount of teeth after missing teeth) is the Ignition Reference Angle. On a 36-1 trigger wheel, each tooth equates to 10 degrees. 36 x 10° = 360°. The Ignition Reference Angle needs to be at least 10° higher than the maximum amount of timing used. 7 teeth is 70° of Ignition Reference Angle, which allows you up to 60° of timing advance (in the Base Timing Table). 6 teeth is 60° of Ignition Reference Angle, which allows you up to 50° of timing advance (in the Base Timing Table). On a 60-2 trigger wheel, each tooth equates to 6 degrees. 60 x 6° = 360°. The Ignition Reference Angle needs to be at least 10° higher than the maximum amount of timing used. 12 teeth is 72° of Ignition Reference Angle, which allows you up to 62° of timing advance (in the Base Timing Table). 11 teeth is 66° of Ignition Reference Angle, which allows you up to 56° of timing advance (in the Base Timing Table). 10 teeth is 60° of Ignition Reference Angle, which allows you up to 50° of timing advance (in the Base Timing Table). 9 teeth is 54° of Ignition Reference Angle, which allows you up to 44° of timing advance (in the Base Timing Table). It gets confusing because for a missing tooth type crank trigger, the EFI software uses the term "TDC Tooth Number" to describe the Ignition Reference Angle. Which is fine, since the amount of teeth (after the missing teeth) is more a definitive method to identify it. http://www.masterenginetuner.com/top...all-fails.html (Crank Reference Angle Importance) UPDATE: The new V4+ EFI software allows the Ignition Reference Angle to be changed from −360° to +360° BTDC on # 1. cylinder. This also eliminates the requirement to alter the Firing Order in Ignition Parameters for some unusual applications. http://forums.holley.com/showthread....m-Sensor-Setup (Crank & Cam Sensor Setup) * There's an updated version of "Crank & Cam Sensor Setup" in the Holley EFI software. On the top Toolbar, click "Help" & "Contents". It's listed in the Help topics. * |
![]() Vibration Damper Timing Marks The following information is only if you decide to put timing marks on the damper (#1 cylinder TDC identification & 30° example): If necessary, use a spark plug hole type piston stop & degree wheel to first establish TDC, then make a damper mark at 30°. FYI: This procedure can also be used to correctly install/position a crank trigger kit/cam sync unit at 60°, 180°, 195°, etc. (LINK). If using spark plug type piston stop, some people remove rocker arms from # 1 cylinder to avoid the risk of valves contacting tool. Also, remove all spark plugs for easy turning force (no compression) to prevent damage from harsh piston-to-tool contact. There's nothing wrong with installing a timing tape. Just ensure it's the correct one for your diameter damper. You don't necessarily need a timing tape, because both timing synchronizations can be performed with one timing mark. Multiply the damper diameter by 3.14159 (Pi), then divide by 360°. The answer is the distance in inches for one degree. For a 30° timing mark, multiply this value by 30. Cut out this distance on a strip of paper to avoid a straight line measurement. |
(Read how to check & adjust rotor phasing further below on this page.)
The crank sensor sliding bracket, now does the task that turning the distributor once did.
http://www.dragstuff.com/techarticle...ger-setup.html (Crank Trigger Setup & Information)

![]() MSD Magnetic Pickup Polarity Testing: If you’re not sure about the polarity of the pickup you are using, there is a simple test you can perform by checking the engine’s timing. Check the timing with the pickup wires connected one way, then swap the wires and check the timing again. You will notice that the timing changes significantly and may appear very erratic. The correct connection depends on the ignition control that is being used. Read page 2: https://documents.holley.com/techlibrary_pickups.pdf (MSD Magnetic Pickup Testing) Analog: If using an analog controlled MSD 6A, 6T or 6AL series, SCI series, 7AL series, MSD 8 or 10 or Blaster Ignition, the correct connection is when the timing is retarded. Digital: If using an MSD Digital-6 or Digital-7 Plus, or the Programmable Digital-7 Ignition Controls, the correct connection is when the timing is more advanced. |
![]() Testing the MSD CD ignition box ground trigger. Points Output - white wire & Magnetic Pickup - violet/green triggering: https://www.msdperformance.com/suppo...ng_techniques/ (Troubleshooting Info) Ensure the distributor's rotor-phasing is correct: http://documents.msdperformance.com/8644_tb.pdf (MSD Rotor-Phasing Document) MSD has a good video on why it's important: http://www.youtube.com/watch?v=aWMlNwGW0tM (MSD Tech Rotor-Phasing Video) For naturally aspirated engines, the rotor is usually phased halfway between minimum & maximum amount of timing advance used. For forced induction engines, the rotor is usually phased at maximum boost retard, because that's when cylinder pressure is the greatest. |
![]() 8.6 Magnetic Crank Pickup - Holley EFI Wiring Manual If running a magnetic pickup, either a crank trigger or a distributor: To run just a magnetic pickup crank input and no camshaft input, PN 558-303 should be purchased. If a cam sync input will be used as well, it is recommended to use PN 558-306 which will contain wiring for both the crank and cam sensor inputs. It is critical that properly installed shielded and grounded cable is used when using a magnetic pickup, or it is likely that EMI will disturb the crankshaft signal. Both PN 558-303 and 558-306 come with the proper cabling. It must be installed properly as well. Make sure that the shield is properly grounded which requires it being grounded at the ECU with that ground maintained through the ignition adapter connection. FYI: The MSD 2-pin connector (LINK/LINK/LINK/LINK/LINK) is a TE Connectivity, Commercial Mate-N-Lok, Free-Hanging #1-480318-9 Plug Housing & #1-480319-9 Cap Housing. Note: The end user must supply the proper connectors/terminals for the crankshaft & camshaft sensors they choose to use with their Holley EFI system. Note: If using an MSD Flying Magnet 4x crank trigger kit, it's highly recommended to use Holley's 554-118 Hall-Effect replacement (direct-fit) crank sensor. |
![]() "Enable Static Timing Set" Discrepancy: I don't recommend using the Enable Static Timing Set to check the Cranking Timing (fuel injector harness temporarily disconnected). Sometimes (although a rare occurrence) enabling the Static Timing Set indicates the timing isn't synchronized at idle; even though the idle timing has just been physically synchronized (by turning the distributor or adjusting the crank sensor). This is usually due to the trigger wheel being off a little bit, and/or an inaccurate EFI software setting in Ignition Parameters. Either way, it's an installation error or a user EFI software setting error. Example: I once helped a Holley DIS user who had the 60-2 trigger wheel off a tooth or two. This caused the "TDC Tooth Number" (in the EFI software) to be inaccurate, which resulted in a "Enable Static Timing Set" discrepancy (at idle) when used. Once corrected, the "Enable Static Timing Set" matched the idle timing when enabled & disabled. This procedure is foolproof and actually confirms itself: 1st, temporarily disable the Idle Spark control (Idle ICF), and synchronize the timing at idle. (Ensure all timing modifiers are inactive.) 2nd, activate the Enable Static Timing Set, and confirm the idle timing is still synchronized. (I use a static value of 25° or 30°.) 3rd, momentarily rev the engine to check timing synchronization at higher RPM, using the Inductive Delay. (Adjust as necessary.) 4th, disable the Enable Static Timing Set and enable the Idle Spark control. Again, this is the same procedure outlined in this timing synchronization tech page (LINK). |
![]() "2D Table" vs "Simple" Target Air/Fuel Ratio Table & Base Timing Table The Target Air/Fuel Ratio Table & Base Fuel/Timing Table (and MAP kPa & RPM axes/scales) should be configured using the Sniper/Terminator X EFI software: In the Sniper/Terminator X EFI software (LINK), Target Air/Fuel Ratio Table (Fuel ICF) & Base Timing Table (Spark ICF), select "2D Table" Type (not "Simple"). The Target Air/Fuel Ratio Table & Base Timing Table can then be properly configured & tuned for any engine. I always suggest taking notes of your current distributor's ignition timing specs/curves beforehand, and then program the Base Timing Table accordingly. https://www.holley.com/support/resou...Fuel_Injection (Terminator X EFI Software & Holley 558-443 CAN/USB Dongle) https://forums.holley.com/showthread...679#post100679 (Holley Sniper & Terminator X EFI Optional Comm/Data Cable Accessories) https://www.efisystempro.com/efi-pro...timing-control (EFISystemPro.com - ECU Timing Control, From Simple To 2D Table) |
![]() Ignition Timing Cylinder Sequence Verification Ensure the Firing Order is entered correctly in Ignition Parameters (System ICF). Before the initial start, disconnect the fuel injector harness and verify at least, the first four cylinders in the firing order using a timing light. If your cylinders are firing in 90° intervals BUT in the wrong sequence, the coil harness is connected wrong (at the ECU or at the coil packs). Hopefully you have a fully degreed balancer or at least markings every 90°: 1st cylinder, in firing order, should fire at 0° (or 15° - add whatever your cranking timing is) 2nd cylinder, in firing order, should fire at 270° (or 285° - cranking timing added) 3rd cylinder, in firing order, should fire at 180° (or 195° - cranking timing added) 4th cylinder, in firing order, should fire at 90° (or 105° - cranking timing added) 5th cylinder, in firing order, should fire at 0° (or 15° - cranking timing added) 6th cylinder, in firing order, should fire at 270° (or 285° - cranking timing added) 7th cylinder, in firing order, should fire at 180° (or 195° - cranking timing added) 8th cylinder, in firing order, should fire at 90° (or 105° - cranking timing added) |
![]() Troubleshooting Holley's DIS/CNP/COP smart coils, with a multimeter (ECU triggering): They have a main +12V & chassis ground, and an ECU triggered power & ground. The ECU ground trigger (B14) is common to all the coils, and tied together in the harness. The ECU triggered +5V power (B21, B22, B23, B24, B15, B16, B17, B18) is obviously individually wired to each coil. Holley's 8-cylinder DIS only uses four of the eight ECU triggers (waste-spark); B21 is always for # 1. Holley's 8-cylinder CNP/COP uses all eight ECU triggers (coil per cylinder); B21 is always for # 1. Using your multimeter, check for a pulsed 5 volt trigger when cranking the engine. You may need to use the Peak Hold function on some multimeters. Switch off the Auto setting on the multimeter. Also, ensure the two cylinder head ignition ground wires are attached. Check CNP ignition coil wiring: LINK & LINK. The ECU triggered power (B21, B22, B23, B24, B15, B16, B17, B18) is individually wired to each coil. Holley's 8-cylinder CNP/COP uses all eight ECU triggers. B21 is always cylinder #1, B15-cylinder #2, B22-cylinder #3, B16-cylinder #4, B23-cylinder #5, B17-cylinder #6, B24-cylinder #7, B18-cylinder #8. FORD engine cylinder numbers: ![]() GM & CHRYSLER engine cylinder numbers: ![]() |
https://www.jcna.com/ignition-advanc...requirements-0 (Ignition Advance Curve Factors)
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